The aim of this research is to explain sensory function in simple mechanoreceptors in terms of biophysical mechanisms at the cellular level, using the large bipolar neurons of the campaniform sensilla of large insects as the main experimental preparation. There are two specific objectives: (1) To explain the electrogenesis of generator current in terms of specific ionic currents as functions of mechanical strain; (2) To show how mechanical coupling, electrogenesis, and impulse initiation contribute to the sensory code. The principle methods, most of which are already in use, or are in advanced stages of development, include: (a) punctate mechanical stimulation with sinusoidally modulated force; (b) linear and quasi-linear analysis with on-line computer to study time-dependent relationships between force, deformation, receptor potential and impulse frequency to identify components of sensory adaptation; (c) a compliance microprobe based on a mechanical loading principle to measure compliance and instantaneous deformation; (d) receptor potential measurement through the intact cuticle of the cochroach leg; (e) conventional intracellular recording in the dissected leg; (f) current injection, and voltage clamping (to be attempted), to identify ionic conductances and reversal potentials; (g) perfusion with strophanthidin and other active transport inhibitors, and stimulants, to investigate the role of active transport in generator current production; (h) histochemical tests for the elastic protein resilin toward interpreting the observed compliances.